import java.util.Stack;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: hp
 * Date: 2024-03-30
 * Time: 16:58
 */
public class Test {
    public static void main(String[] args) {
        Stack<Integer> stack = new Stack<>();

        //入栈
        stack.push(12);
        stack.push(23);
        stack.push(34);
        stack.push(45);


        //出栈
        //stack.pop();
        Integer x = stack.pop();
        System.out.println(x);


        /*Integer x1 = stack.peek();
        System.out.println(x1);
        Integer x2 = stack.peek();
        System.out.println(x2);*/

    }
}
